Kenan ÇADIRCI, Özlem Özdemir TOZLU, Hasan TÜRKEZ, Adil MARDİNOĞLU

The in vitro cytotoxic, genotoxic, and oxidative damage potentials of the oral artificial sweetener aspartame on cultured human blood cells

Background/aim: Aspartame APM, L-aspartyl-L-phenylalanine methylester is a low-calorie, nonsaccharide artificial sweetener widely used in foods and beverages. When metabolized by the body, APM is broken down into aspartic acid, phenylalanine amino acids, and a third substance, methanol. Since the amino acid phenylalanine serves as a neurotransmitter building block affecting the brain, and methanol is converted into toxic formaldehyde, APM has deleterious effects on the body and brain. Thus, its safety and, toxicity have been the subjects of concern ever since it was first discovered. Although many studies have been performed on it, due to the presence of conflicting data in the literature, there are still numerous question marks concerning APM. Therefore, the safety of aspartame was tested using in vitro methods. Materials and methods: We aimed to evaluate the in vitro cytotoxic effects by using 3- 4,5-dimetylthiazol-2-yl -2,5-diphenyltetrazolium bromide MTT and lactate dehydrogenase release tests, genotoxic damage potential by using chromosome aberration CA assay, and antioxidant/oxidant activity by using total antioxidant capacity TAC and total oxidative stress TOS analysis in primary human whole blood cell cultures. Results: The results of the MTT test showed that APM led to significant decreases in cell viability in a clear concentration-dependent manner. Moreover, an increase in CA frequency was found in the cells treated with APM. However, APM treatments did not cause any significant changes in TAC and TOS levels in whole blood cultures. Conclusion: Overall, the obtained results showed that APM had genotoxicity potential and a concentration-dependent cytotoxic activity in human blood cells.

Keywords:

Aspartame cytotoxicity, genotoxicity, antioxidant activity, human whole blood cultures,

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